The present invention relates to a process for determining operating conditions of a motor vehicle from output signals of a sensor for a relevant operating variable. The output signals are supplied directly and in parallel via an analyzer with respect to a relevant parameter, to an evaluating device.
This type of process is known from German Published Unexamined patent application No. 3,007,747 and has the purpose of obtaining the information contained in the output signal of the sensor concerning an additional operating variable, with an objective of saving a separate sensor for this additional operating variable. The sensor, in this known process, has the purpose of determining a physical value, such as a rotational speed, a path, an angular positionor a pressure, and receiving, as additional information, a statement concerning, for example, the temperature or an additional pressure. The primary information contained in the output signal of the sensor and the additional information are used for controlling the access to a characteristic curve or a characteristic diagram.
An objective of the present invention is to provide a significantly improved process for determining operating conditions of a motor vehicle with respect to the amount of the obtained information as well as with respect to the conversion into measures resulting from it.
This and other objectives are achieved in the present invention in a process for determining operating conditions of a motor vehicle from output signals of a sensor for a relevant operating variable, these output signals being supplied directly to an evaluating device in parallel to this direct supply, supplied to the evaluating device via an analyzer with respect to a relevant parameter, this process comprising the steps of analyzing, via at least one additional analyzer with respect to an additional parameter, the output signal. The process also includes the steps of supplying the additionally analyzed signal to the evaluating signal in parallel to the directly supplied output signal, and generating in the evaluating device an at least two-dimensional pattern, the shape of this pattern being determined by the output signals of the sensor and of the analyzers. The pattern is compared with preset patterns, and an indicating measure is provided when the limit pattern for a critical operating condition is approached.
Of central importance for the invention is the at least two-dimensional pattern that is known from the field of speech recognition. In speech recognition, the output signal of the sensor is evaluated by the analyzers with respect to all or to a large part of the information contained in it. Each information influences the pattern in a characteristic way. The comparison of the characteristics of the current pattern with the characteristics of the present pattern will then result in a concrete statement as to what extent the current operating condition can still be tolerated or to what extent it has approximated a critical operating condition.
The present invention may, for example, be applied to a pressure sensor that determines the loading of a chassis spring of a motor vehicle at the point of support. The additional information contained in it, such as the fundamental frequency, the excitation frequency, the amplitude and the change of these frequencies and amplitudes, in addition to the primary information of the pressure are converted into a corresponding pattern form. The comparison of the current pattern with the preset patterns takes place by the conventional process of image comparison, for example, by a correlation analysis. In correlation analysis, the correlation coefficient represents a precise statement concerning the conformity of the current pattern with a preset pattern. In addition, other processes for the image analysis are also contemplated, such are used, for example, within the framework of photographic images for the automatic focusing of a picture.
In contrast to other known processes for the determination of operating conditions, no characteristic diagram is required in the present invention that requires a lot of storage space, since the characteristics of the pattern can be compressed considerably without any significant loss of content. Each operating condition can be recognized in a picture and because of the characteristic picture form, early discloses a tendency of reaching a critical operating condition. As a result, it becomes possible to trigger in time, warning and display measures for a critical operating condition and to securely avoid this operating condition.
In certain preferred embodiments, the preset patterns are generated under defined operating conditions in a preceding learning step and thus, a realistic picture of the currently occurring operating conditions and their effects on the information is obtained. In contrast to, for example, the use of a characteristic diagram that as a rule is not obtained by means of the respective object, but is preset from the start, this measure has the advantage of obtaining the pattern individually and thus at any time obtaining a precise statement concerning the current operating condition.
The acoustical warning provided in certain preferred embodiments expands the practical benefit of the invention because the user of the motor vehicle receives an additional aid for avoiding a critical operating condition by corresponding countermeasures.
Finally, in certain preferred embodiments, at least one additional sensor is included, the output signal of this additional sensor controlling access to the preset patterns. This provides the localization of the respective current operation condition by the additional operating variables sensed by the additional sensor and thus, accelerating and making more precise the finding of the appropriate preset pattern. This is of considerable significance particularly for fast changes of the operating condition because even then, the respective relevant preset pattern can be found within a short and still sufficient amount of time.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.